Conventional networks route telephone signals over an internet protocol (IP) network by converting channel associated signals (CAS) into IP signals using a CAS device. The CAS device serves as a type of gateway between the public branch exchange (PBX) telephone system and the IP network. The CAS device is connected to one or more PBX systems through a line such as a T1 line, for example. The T1 line may connect the CAS device to multiple PBX telephone systems. Each PBX system may have its own specific CAS protocol. However, only one CAS protocol can be used with the line. In order to change the line's CAS protocol, the line must be taken out of service. Alternatively, the CAS module must be able to support a large number of CAS protocols.
It is extremely difficult to support many, if not all, CAS protocols using a single CAS module. Furthermore, if a given protocol is upgraded, the CAS module must be upgraded by taking the corresponding telephone lines out of service.